This invention relates to a control system for a humidifier, particularly to one having a variable resistor with an on/off switch function for turning on and off a supersonic oscillator so as to lower the cost of a humidifier.
A known conventional control system for a humidifier shown in FIGS. 1 and 2, includes an AC input terminal, an interactive switch SW consisting of a variable resistor VR and a silver contact point, a neon lamp L and an AC fan F for heat dispersing connected in parallel to the interactive switch SW, a transformer T for lowering the voltage, a bridge rectifier B1 for changing AC into DC, two resistors R1, R2 connected in parallel to the input and the output 1 and 2 of the bridge rectifier B1, a contact point 3 between the two resistors R1, R2 connected to one end of the variable resistor VR, two inductance coils L1, L2 and the base of a transistor Q1 connected in series to the variable resistor VR. Further, an ultrasonic oscillator circuit provided between the inductance coil L1 and L2 and consisting of a capacitor C1 and an ultrasonic oscillator H., and a capacitor C2 connected between the capacitor C1 and the ultrasonic oscillator H to divide current. Then the emitter 5 of the transistor Q1 is connected to another inductance coil L3, and a diode D1 is connected between the emitter 5 and the inductance coil L3 to divide the current, and a capacitor C3 is connected to the end of the circuit of the control system.
The known conventional control system for a humidifier consists the switch SW and the silver contact point to function as a general switch for the control system for a humidifier. So the conventional control system for a humidifier has a disadvantage of high cost.
The objective of the invention is to offer a control system for a humidifier of a lower cost than that of the conventional ones.
One feature of the invention is a variable resistor used in the control system also having on/off function, enabling the control system more quickly operated.
Another feature of the invention is a DC fan used instead of an AC fan for dispersing heat to lower the cost of the control system.